I would be interested to know whether folk walk on after dark much? Or do you always stop and set camp while there is sun light available?
If I'm hoping to get to a loch or some water source I'll usually keep going well into the dusk and pitch where I intended to pitch. However I'll often look at the time a few hours before, realise I'll be arriving in the dark and just hoof it a little faster instead.
As for intentional walking in the dark, I prefer to start off in the dark in the early hours than finish in them. Not sure if it's because I feel I'm happier with being at my most 'fresh' (usually after an early morning coffee) when I've got the greatest chance of a slip or fall due to darkness, or whether I just don't feel like my body ever relaxes and wants to fall asleep easily when I've made camp late at night.
It's worth making a habit of doing some nighttime walking when you hike though, even if it's just to keep your navigation fresh and allow you to be more confident if you need to stay out unexpectedly.